Sucker rod coupling



Feb. 2, 1965 w. E. HOWARD 3,168,340

SUCKER ROD COUPLING Filed Jan. 10, 1961 2 Sheets-Sheet 1 Fig. 2

William E Howard INVENTOR.

BY (Wavy 3% Feb. 2, 1965 w. E. HOWARD 3,168,340

SUCKER ROD COUPLING Filed Jan. 10, 1961 2 Sheets-Sheet 2 Fig.3

William E Howard United States Patent Office 3,168,340 Patented Feb. 2, 1965 3,168,340 SUCKER ROD COUPLING William E. Howard, Victoria, Tex. ,7 (36 16 Lily St., Bay City, Tex.) Filed Jan. 10, 1961, Ser. No. 81,832 6 Claims. (Cl. 287-119) This invention comprises a novel and useful sucker rod off and on tool and more particularly relates to an assembly for providing a safe and secure but easily engageable or disengageable connection between the sucker rod string sections or the sucker rod string and a pump plunger.

In certain types of deep well pump constructions it is desirable to be able to effect a removal of the sucker "rod string which operates the pump from its attachment to the pump in order to remove the sucker rod string for various purposes while leaving the pump unit in its submerged position in a well bore, flow tubing or the like. At the same time, it is vitally important that the connection of the sucker rod string to the pump plunger shall be so secure as to avoid substantially any possibility of an accidental or unintentional disconnection of the sucker rod string from the pump plunger.

It is therefore the primary object of this invention to provide a connecting device or mechanism which will effect a secure engagement of the sucker rod string sections either to themselves or to the pump plunger where the device is employed with a minimum danger of accidental parting of the sucker rod string and yet which will readily enable the sucker rod string to be disconnected when desired.

An important feature of the invention is that the outside diameter of this device is no larger than that of any other similar device on the market today, but has a greater wall thickness which will prolong the life of the device due to the fact that it will stand more wear and abuse before exposing any of the internal working parts. i It is a further and subordinate object of the invention to provide a coupling mechanism in accordance with the foregoing object which shall be of an extremely simple and durable construction consisting of a minimum number of separate parts and which shall be capable of quick and easy assembly or disassembly by unskilled labor.

A still further object of the invention is to provide a coupling mechanism in accordance with the precedingobjects which shall be extremely resistant to the detrimental and corrosive eiiects of electrolysis under conditions of use in a well bore.

Although the primary reason for this invention is for oil well application as a sucker rod off and on coupling, it is also generally applicable wherever a quick disconnection under strain, tension, or a load be desired as a safety application or an emergency condition; the application of the invention to other environments being made possible by merely changing connecting ends in any manner desired without changing the working mechanism in any manner.

These together with other objects and advantages which will become subsequently apparent reside in the details of construction and operation as more fully hereinafter described and claimed, reference being had to the accompanying drawings forming a part hereof, wherein like numerals refer to like parts throughout, and in which:

FIGURE 1 is a view in vertical section .through va portion of a well bore anda well casing or flow tubing therein and showing the manner in which the detachable coupling mechanism of this invention is incorporated into the sucker rod string for connection to a pump plunger;

FIGURE 2 is an enlarged view in vertical central section through the detachable coupling mechanism of this invention showing the position of the parts when the connect ion is in its locked position; I

FIGURE 3: is an exploded perspective view of certain of the internal'parts of the cou plingmechanism;

FIGURES 4-6 are detail views taken inhor' izo'htal sec tion substantially upori' the planes indicated by the secf' tion lines 4-4, 5-5, and 6-6, respectively, of FIG- URE 2; and

FIGURE 7 is a perspective View of the spring-loaded locking member of the detachable connecting mechanism.

Referring first to FIGURE 1 it will be observed that the numeral 10 indicates generally the detachable connecting device forming the subject matter of this invention which is shown as being connected to an upper sucker rod string 12 and to the upwardly projecting stem 14 of a pump member 16 or other element which is to be reciprocated by the sucker rod string. The sucker rod and pump are shown disposed in a tubing or casing 18 which comprises the flow tubing within a well bore 20 projected downwardly from the surface of the earth into a productive formation from which fluids are to be recovered. It is to be understood that the outside diameter of the device 10 is uniform throughout its length.

The detachable mechanism 10 forming the subject matter of this invention comprises a means by which the sucker rod string 12 is releasably secured to the upwardly projecting plunger or stem 14 of an element 16. The various internal elements of the device 10 are shown in FIGURE 3 while FIGURE 2 shows the assembled relation of the same.

Referring next to FIGURE 2 in more detail it will be observed that the detachable coupling device 10 consists of a cylindrical body 30 having an opening extending throughout its entire length, with the upper end of this opening being internally threaded as .at 32. A closure plug 34 having a diametrically reduced externally threaded lower extremity 36 is engaged in the upper end of the opening in the body 30 and functions to provide a closure for the upper end of the opening throughfthe body as Well as a means by which the body is connected to the sucker rod stiing 12. For *this last mentioned purpose, the plug 34 has an upwardly projecting diametrically reduced externally threaded stem .or pin 38 which is received in the internally threaded socket or recess, not shown, in the adjacent end of the sucker rod string 12.

As will be further noted, the lower portion of the closure plug 34 is provided with an axially upwardly extending bore 40 therein forming a recess for a purpose to becomesubsequently apparent.

Slidably .and removably received in the open .lower end of the body 30 is a connnector element 42 having at its lower end an internally threaded bore 44 by means of which a screw threaded engagement with the stem or plunger 14 is effected. In operation the engagement of the pin or stem 38 of the closure plug 34 with the sucker rod string 12 and the engagement-of the threaded bore 44 of the connector member 42 :with the member 14 is nornally a substantially permanent one, with the releasable coupling-action of therdevice being eifected by the releasable seating engagement ,of the connector member 42 within the body30 as set forth hereinafter.

Referring now withmore particularity to FIGURE 2 in conjunction with FIGURE 3 it will be noted that the connectormember 42 includes a lower cylindrical main .body portion having a diametrically reduced stem or neck portion 46 rising therefrom which neck portion in turn at its upper extremity has a head'portion 48 thereon. This 'head portion is of a relatively flat plate-like configuration being of less thickness than the diameter of the stem or neck portion 46 to which the-opposite sides of the head 48 are secured as :by'thecurvedconverging surfaces 59, while the head portion is of a greater width than the diameter of the stem or neck 46 to thus project laterally to opposite sides of the same. The lower end of the neck portion 46 is connected to the main body portion 42 of the connector member by a generally circular enlargement 52 which has a conical upper surface 54 merging into the neck 46 together with a' cylindrical lower surface 56. In this lower surface there is provided a circumferentially extending groove or channel 58 in which is received an O-ring 60 of any suitable non-metallic character. The junction of the cylindrical portion 52 with the cylindrical body 42 results in the formation of a horizontal annular surface 62 which is adapted to engage and abut against the end surface of the lower end of the body 30 as shown in FIG- URE 2.

The lower portion of the opening through the body 30, as shown in FIGURE 6, is non-circular in cross-section and is indicated by the numeral 64. This opening is of sufiicient length and width to enable passage of the head 48 therethrough and to slidingly receive the stem 46 therein. The arrangement is such that when the non-circular head 48 is caused to register or coincide with the noncircular portion 64 of the opening, the connector member 42 may be moved into or outwardly of the opening in the lower end of the body and thus effect an engagement or disengagement with the latter.

At the upper end of the non-circular opening 64 the body 30 is provided with seating surfaces upon which the lower portion of the head 48 is adapted to rest when the head is rotated 90 from its position in registration with the non-circular portion 64 through which the head may be passed. In this rotated position indicated in FIGURE 5, the diametrically enlarged portion of the head 48 thus straddles the non-circular bore 64 and rests upon the seat 66 thereby preventing withdrawal of the head through the opening and thus preventing disengagement of the connector member 42 from the body 30. In this position the two separable components 30 and 42 of the connecting mechanism of this invention are retained in their connected position.

The lower portion of the bore 64 is provided with a conical sealing surface 70 which is complementary to the surface 54 and is adapted to rotatingly engage the latter, while there is provided a further cylindrical surface/72 which slidingly receives the cylindrical surface 56 and O-ring 60. In this manner a fluid tight seal is established by means of the 'O-ring and/ or the cooperating surfaces of the complementary surfaces 70, 54 to prevent the ingress of fluid into the interior of the device.

Further, the presence of the non-metallic O-ring forms an insulation serving to interrupt the continuous electric path of travel over the metallic components of the device thereby greatly minimizing the effect of electrolysis present in some wells in which the body may be immersed at this location thereby contributing to the longer life of the device.

A resilient means is provided for yieldingly urging the head 48 and the connector member 42 downwardly in the body 30 so as to retain the head 48 upon the seat 66. This resilient means includes a compression spring 76 having its upper end seated against the closure plug 34 in the recess 40 therein while the lower end of the spring is engaged against a washer or abutment plate 78 which is secured to the upper end of a cylindrical plunger 80. This plunger has an upstanding boss 82 received within the lower end of the spring 76 and constituting a guide means for the latter, this boss also serving to retain the washer 78 upon the plunger. As shown best in FIGURE 4, the plunger 80 is cylindrical and is slidably received within the cylindrical portion 83 of the upper end of the opening extending through the body 30. However, cooperating vertically extendingv or longitudinally extending guide ribs 84 within the body 30 cooperate with vertically extending guide channels 86 formed in the sides of the plunger 80 to thereby limit the plunger to 4 verticalreciprocation within the body and prevent relative rotation therebetween.

As will be best apparent from FIGURE 7, the lower surface of the plunger is provided with upwardly dished recesses forming cam surfaces which cooperate with complemental diametrically oppositely disposed cam surfaces 90 on the upper surface of the head 48.

The arrangement is such that the pressure of the compression spring 76 exerted downwardly upon the body of the plunger 80 serves to urge the latter downwardly in the cylindrical portion 83 of the bore through the body and causes an engagement of the complementary cam surfaces 88 of the plunger with the surfaces 90 of the head 48. This engagement tends to center the diametrically oppositely extending surfaces 90 of the head 48 in diametrically opposite recesses 88 in the bottom surface of the plunger 80 and since the latter is restrained against rotation by engagement of the keys or splines 84 in the channels 86, there is thus a resilient but yieldable tendency to also retain the head 48 against relative rotation. At the same time, the spring presses the bottom surface of the head 48 against the seat 66 previously mentioned. In this position the diametrically oppositely projecting portions of the head 48 as shown in FIGURE 2 engage upon the seat 66 and thus prevent withdrawal of the connector member 42 from the lower non-circular portion 64 of the opening through the body 30. At the same time, the force of the spring 76 and the engagement of the complementary camming surfaces 88 and 90 tend to prevent rotation of the head from the seated osition upon the seat 66 to a registering position with the lower portion 64 in which the head, stem and the connector member 42 could be withdrawn from the body.

The tension of the spring 76 is such that with the part in the position shown in FIGURE 2 the detachable con= nector member 42 is securely locked in the body 30 so that the sucker rod string 38 is securely connected to the plunger or element 16.

It is thus evident there has been provided a secure con nection between a sucker rod string and a member to be actuated thereby which is capable of preventing as: oidental separation of these elements but can be readily adjusted to disconnect a sucker rod string from the member 16 coupled thereto and enable the sucker red string to be withdrawn or replaced as desired. Further, the O-ring 60 efiectively prevents the deterimenytal effects of electrolysis upon the metallic cooperating elements 42, 30 of the device when the latter is immersed in well fluids.

The O-ring 60 elfectively preventsthe detrimental effects of electrolysis from entering into the metallic cw operating elements in 42, 30 of the device, thereby protecting the inner working parts of the device from same a when the latter is immersed in a well where these conditions are found to be present.

It is also evident that a disconnection can be made O f the sucker rod string sections joined by this device merely by making a partial turn of in either direction with the weight of the spring resting upon the device or with a tension applied thereto.

The foregoing is considered as illustrative only of the principles of the invention. Further, since numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation shown and described, and accordingly all suitable modifications and equivalents may be resorted to, falling within the scope ot the invention as claimed.

What is claimed as new is as follows:

1. A sucker rod coupling comprising the combination of (a) a vertically elongated body with a releasably attached connector element,

(b) said body having an opening extending upwardly from its bottom end and including an upper portion and a non-circular lower portion,

(c) said upper portion being diametrically enlarged relative to said lower portion and constituting a locking chamber having a bottom Wall,

(c!) said bottom wall including a shouldered seat extending laterally outwardly from the wall of said lower portion,

(e) said connector element having upper and lower pontions,

(f) said connector element upper portion having a non-circular head complementary in cross-sectional shaped and size to said opening lower portion and movable therethrough into and out of said locking chamber when said head is rotationally registered with said opening lower portion,

(g) said head including a laterally projecting portion seating upon said shouldered seat and preventing withdrawal of said connector element through said opening lower portion when said head is in non registry with the latter,

(h) said connector element lower portion having means for attachment to a member to be actuated by a sucker rod,

(1) resilient means engaging said body and said connector element and biasing said laterally projecting portion against said shouldered seat and yieldingly resisting rotation of said connector element,

(j) said resilient means comprising a plunger disposed for sliding movement in said opening upper portion and a spring engaging said plunger,

(k) guide means on said body and plunger preventing relative rotation therebetween,

(I) said plunger having abutting engagement with said connector element,

(m) said plunger and connector element having complementary cooperating recesses and projections provided with cooperating cam surfaces yieldingly maintained in engagement by said spring,

(n) said plunger comprising a vertically elongated body with said spring engaging its top surface and having said complementary recesses disposed upon its bottom surface,

(0) said camming surfaces on said connector element and said plunger recesses extending radially and being inclined outwardly and downwardly and centering the upper end of the connector element in the lower end of said plunger whereby relative rotation of said connector element with respect to said body moves said plunger upwardly and permits disassembly of said body from said connector element.

2. The combination of claim 1 wherein said opening comprises a continuous passage extending entirely through said (body and with the plunger being removable through the upper end of said opening, a closure plug for the upper end of said opening comprising means for connecting said body to a sucker rod and an abutment for said spring.

3. The combination of clairn 2 wherein said closure plug has a downwardly opening bore therein, said spring having its upper portion received in said bore.

4. The combination of claim 1 including cooperating seating surfaces on said connector element and within the lower end of said opening lower portion establishing a positive seating engagement therebenween.

5. The combination of claim 4 wherein said body has a depending flange, said depending flange and said connector element below its seating surface having complementary cylindrical engaging surfaces enclosing said seating surfaces.

6. The combination of claim 5 including an O-ring disposed between and sealingly engaging said cylindrical surfaces.

References Cited in the file of this patent UNITED STATES PATENTS 322,286 Hemje July 14, 1885 1,194,793 Styers Aug. 15, 1916 1,531,463 Vincent Mar. 31, 1925 1,645,428 Hosmer Oct. 11, 1927 1,968,075 Ewald July 31, 1934 2,795,438 Oetiker June 11, 1957 2,889,157 Kolbe June 2, 1959 2,940,787 Goodner June 14, 1960 3,021,160 Hooks Feb. 13, 1962 

1. A SUCKER ROD COUPLING COMPRISING THE COMBINATION OF (A) A VERTICALLY ELONGATED BODY WITH A RELEASABLY ATTACHED CONNECTOR ELEMENT, (B) SAID BODY HAVING AN OPENING EXTENDING UPWARDLY FROM ITS BOTTOM END AND INCLUDING AN UPPER PORTION AND A NON-CIRCULAR LOWER PORTION, (C) SAID UPPER PORTION BEING DIAMETRICALLY ENLARGED RELATIVE TO SAID LOWER PORTION AND CONSTITUTING A LOCKING CHAMBER HAVING A BOTTOM WALL, (D) SAID BOTTOM WALL INCLUDING A SHOULDERED SEAT EXTENDING LATERALLY OUTWARDLY FROM THE WALL OF SAID LOWER PORTION, (E) SAID CONNECTOR ELEMENT HAVING UPPER AND LOWER PORTIONS, (F) SAID CONNECTOR ELEMENT UPPER PORTION HAVING A NON-CIRCULAR HEAD COMPLEMENTARY IN CROSS-SECTIONAL SHAPED AND SIZE TO SAID OPENING LOWER PORTION AND MOVABLE THERETHROUGH INTO AND OUT OF SAID LOCKING CHAMBER WHEN SAID HEAD IS ROTATIONALLY REGISTERED WITH SAID OPENING LOWER PORTION, (23) SAID HEAD INCLUDING A LATERALLY PROJECTING PORTION SEATING UPON SAID SHOULDERED SEAT AND PREVENTING WITHDRAWAL OF SAID CONNECTOR ELEMENT THROUGH SAID OPENING LOWER PORTION WHEN SAID HEAT IS IN NONREGISTRY WITH THE LATTER, (H) SAID CONNECTOR ELEMENT LOWER PORTION HAVING MEANS FOR ATTACHMENT TO A MEMBER TO BE ACTUATED BY A SUCKER ROD, (I) RESILIENT MEANS ENGAGING SAID BODY AND SAID CONNECTOR ELEMENT AND BIASING SAID LATERALLY PROJECTING PORTION AGAINST SAID SHOULDERED SEAT AND YIELDINGLY RESISTING ROTATION OF SAID CONNECTOR ELEMENT, (J) SAID RESILIENT MEANS COMPRISING A PLUNGER DISPOSED FOR SLIDING MOVEMENT IN SAID OPENING UPPER PORTION AND A SPRING ENGAGING SAID PLUNGER, (K) GUIDE MEANS ON SAID BODY AND PLUNGER PREVENTING RELATIVE ROTATION THEREBETWEEN, (L) SAID PLUNGER HAVING ABUTTING ENGAGEMENT WITH SAID CONNECTOR ELEMENT, (M) SAID PLUNGER AND CONNECTOR ELEMENT HAVING COMPLEMENTARY COOPERATING RECESSES AND PROJECTIONS PROVIDED WITH COOPERATING CAM SURFACES YIELDINGLY MAINTAINED IN ENGAGEMENT BY SAID SPRING, (N) SAID PLUNGER COMPRISING A VERTICALLY ELONGATED BODY WITH SAID SPRING ENGAGING ITS TOP SURFACE AND HAVING SAID COMPLEMENTARY RECESSES DISPOSED UPON ITS BOTTOM SURFACE, (O) SAID CAMMING SURFACES ON SAID CONNECTOR ELEMENT AND SAID PLUNGER RECESSES EXTENDING RADIALLY AND BEING INCLINED OUTWARDLY AND DOWNWARDLY AND CENTERING THE UPPER END OF THE CONNECTOR ELEMENT IN THE LOWER END OF SAID PLUNGER WHEREBY RELATIVE ROTATION OF SAID CONNECTOR ELEMENT WITH RESPECT TO SAID BODY MOVES SAID PLUNGER UPWARDLY AND PERMITS DISASSEMBLY OF SAID BODY FROM SAID CONNECTOR ELEMENT. 